The file handle associated with standard input is STDIN. You need not open it. You can read from this filehandle as you do with your filehandle F.

perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'

In reply to Re: How to read the file from stdin using perl? by shmem
in thread How to read the file from stdin using perl? by gopikavi

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